|
|
|
Control of flue gas-air system for fired heaters
based on steady state model |
ZHANG Wei-yong1, LI Ying1, HUANG De-xian1， YI Jia2
ZHANG Zhi-yin2, YANG Xiang-dang2 |
1. Department of Automation, Tsinghua National Laboratory for Information Science and Technology, Tsinghua
University, Beijing 100084, China; 2. Huabei Petrochemical Company PetroChina, Renqiu 062552, China |
|
|
|
Abstract Due to the difficulties in the control of flue gas-air system of fired heater, such as severe nonlinearities, low sensitiveness to control signal which exists widely in the actuators, and high coupling of process variables, it’s not easy to guarantee stability and safety by the dynamic control method. A control strategy adopting steady state model was proposed. The steady state model directly calculates the control move and implements it. Then the controller waits one settling time, and the next control move is calculated using the steady state feedback information if necessary. A sufficient condition for convergence was proved. The method avoids the potential dangerous caused by high frequency adjustment and provides stable control. Automatic control for the whole fired heater unit was achieved by applying the control strategy to the chamber oxygen content and pressure control. Simulation and industrial application show that the control performance is satisfactory. The strategy provides a basis for safe and smooth operation, and further thermal efficiency optimization.
|
|
Published: 01 December 2011
|
|
|
基于稳态模型的加热炉烟风系统控制
由于加热炉烟风系统风量调节执行机构存在较严重的非线性、灵敏度差、变量间强耦合,基于动态的控制系统稳定性和安全性很难得到保障,为此提出采用稳态模型的烟风系统控制方法.利用该模型直接计算出调节量并送至执行机构进行调节,在等待一个稳态响应时间后,如果未能达到控制目标则根据稳定后的调整结果再进行下一次调节.给出了算法收敛的充分条件.该烟风系统控制方法避免了频繁调节所带来的安全隐患,克服了动态反馈控制存在的稳定性难题.将该方法应用于氧含量和负压的控制,实现了加热炉的整体自动控制.仿真研究和现场应用表明,控制效果良好,为加热炉的安全、平稳运行创造了条件,并为进一步的热效率优化提供了基础.
|
|
| ［1］ 钱学麟.管式加热炉［M］.北京:中国石化出版社,2003: 583-640.
［2］ 蒋慰孙,俞金寿.过程控制工程［M］.北京:中国石化出版社,1999: 69-185.
［3］ 赖胜,孙德敏,吴刚,等.常压加热炉的在线燃烧优化［J］.石油化工自动化,2003(2): 23-27.
LAI Sheng, SUN Demin, WU Gang, et al. Online optimization of burning in atmospheric heating furnace ［J］. Automation in PetroChemical Industry, 2003(2): 2327.［4］ 苏成利,李平,张日东,等.预测函数控制在焦化加热炉氧含量控制中的应用［J］.石油化工自动化,2007(2): 33-36.
SU Chengli, LI Ping, ZHANG Ridong, et al. Application of predictive functional control for oxygen content in delayed coking furnace ［J］. Automation in PetroChemical Industry, 2007(2): 33-36.
［5］ 张日东,苏成利,张建明,等.PFCPID控制在加热炉炉膛压力控制中的应用［J］.华东理工大学学报：自然科学版,2006,32(7): 750-753.
ZHANG Ridong, SU Chengli, ZHANG Jianming, et al. Predictive functional control of chamber pressure of coking furnace ［J］.Journal of East China University of Science and Technology: Natural Science Edition, 2006, 32(7):750-753.
［6］ ZHANG R D, LI P, XUE A K, et al. A simplified linear iterative predictive functional control approach for chamber pressure of industrial coke furnace ［J］. Journal of Process Control, 2010, 20: 464-471.
［7］ 张伟勇,吕文祥,黄德先.基于稳态能量平衡的支路平衡控制［J］.计算机与应用化学,2008,25(7): 777-781.
ZHANG Weiyong, LU Wenxiang, HUANG Dexian. A pass temperature balance control for fired heater based on steady state energy balance ［J］. Computers and Applied Chemistry, 2008, 25(7): 777-781.
［8］ 黄德先,张伟勇,吕文祥,等.加热炉热效率多区域智能在线优化控制方法:中国,201010217097.3［P］.2010-07-02.
HUANG Dexian, ZHANG Weiyong, LU Wenxiang, et al. A multizone intelligent online thermal efficiency optimization method for fired heater: CHN,201010217097.3［P］. 2010-07-02.
［9］ 沙天杰.调节阀组性能及应用［J］.中国仪器仪表,2003,23(1): 16-19.
SHA Tianjie. The Capability and application of control valves group ［J］.China Instrumentation, 2003, 23(1): 16-19.
［10］ ZHANG W Y, HUANG D X, WANG Y D, et al. Adaptive state feedback predictive control and expert control for a delayed coking furnace ［J］. Chinese Journal of Chemical Engineering, 2008,16(4): 590-598. |
|
Viewed |
|
|
|
Full text
|
|
|
|
|
Abstract
|
|
|
|
|
Cited |
|
|
|
|
| |
Shared |
|
|
|
|
| |
Discussed |
|
|
|
|
